Extraction of phosphatides, free fatty acids, and the like from glyceride oils



Patented Dec. 11, 1945 EXTRACTION OF PHOSPHATIDES, FREE FATTY ACIDS, AND THE LIKE FROM GLYCERIDE OILS Stephen E. Freeman, Wauwatosa, Win, assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa... a corporation of Pennsylvania No Drawing. Application May 13, 1940,

' Serial No. 334,999

'ZCiaims.

The present invention relates to removal oi. certain materials, notably such materials as lecithin; like phosphatides, free fatty acids and similar constituents from glyceride oils.

One object of the invention is to provide a proc- 88s of simultaneously removing gum-forming or "break forming constituents and free fatty acids from a glyceride oil and notably of vegetable oils, which process is relatively simple and inexpensive in its nature.

This and other objects of the invention will be apparent from consideration of the following specification and the appended claims.

In my copending Patents 2,200,391 and 2,200,390, having the issue date of May 14, 1940, aredisclosed processes of extracting glyceride oils and notably such oils as comprises a mixture of relatively highly unsaturated and more completely saturated glycerides into fractions, upon the basis of the degree of saturation or unsaturation. Such fractionation may be eifected by numerous polar solvents of which furfural is a typical example. In these extractions the polar solvent and the oil are simply intimately contacted by batch or countercurrent process, or by a suitable countercurrent batch operation.

The oils in addition to comprising mixtures of relatively saturated and unsaturated 'glycerides also include in some cases lecithin-like phosphatides, which are of considerable value for various pharmaceutical and industrial purposes.

benefited by such treatment. The selective polar solvent may be simply saturated or partially saturated with the aqueous medium or an excess of the aqueous medium may be employed and in part maintained as a separate liquid phase during the extraction. The oils and the extraction medium may be contacted by countercurrent now in a suitable column or by simple agitation together, followed by subsequent settling or centrifugation. Various polar solvents may be employed in the operation, but the following are considered to be particularly advantageous because they posses a considerable degree of solubility with respect to water:

Table A Hydrooyl Eater Meth l formate 1 51i al c gf Ethy ene glycol dliormate.

Trlacetin Glycol diacetate Methyl malonnte Math 1 oxalate Ethy oxalate n-Propyl alcohol Iso-propyl alcohol Ethylene gl col Propylene g ycol Glycerine Tertiary butyl alcohol Dlmethyl ethynyl carblnol Hydrooyl-O flier Allyl alcohol Ethylene chlorhydrin Glycerol monochlorhydrin a o Beta-hydroxy roplonltrile The oils also include certain percentages of free fatty acids which are applicable to numerous purposes, for example as constituents in artificial resins or as stock for the manufacture of soaps.

The phosphatlde material in some cases is ob- Jectionable in the fractionation of the glyceride oils, because upon contact with a solvent such asfurfural it tends to precipitate out to ionn a sludge which collects at 'the inter face between the solvent and the oil body. This sludge may .tend to clog the extraction apparatus and for that reason it is desirable preliminarily to remove it before the oil is subjected to fractionation. The phosphatides may be removed from the oil by washing with water or with an aqueous solution or water and alkaline salt, such a sodium carbonate. However, such process is not eflfective to remove the free fatty acids also contained in the oi v According to provisions of the present invention it is proposed simultaneously to remove free fatty acids and sludge-forming constituents such as lecithin and the like from glyceride oils by subiecting the latter to intimate contact with a solu- Beta-ethoxy et yl lactate Beta-ether ethyl glycolate Furi'urnl a coho 2-nitro-1-butanol Diethyl ammo ethanol Propylene chlorhydrin HydrooyF-Estor Meth l glycolate Ethy glycolate Beta-h roxy ethyl acetate Ethyl uctate Mono acetin Diacetin Hydrant-Carbonyl Methyl butanolone Acetyl meth l carbinol Diacetone a cohol Methyl acetyl lactate Hydraoyl ether Ether Dioxane Dloxolane DimethylCellololvo Dimethoxy tetragiycol Acid Formic acid Acetic acid Propionic acid Isobutyric acid Ester-Other Methyl Celloaolve formats Methyl Celloaoivo acetate Methyl Cellosoive adipate Dimetthyl Cellosolve succina e Eth l n-methyl earbamato Met yl chloroacetate Methyl cyanoacetate Ester-Carbonyl Methyl levuilnate Eth levulinato Met l acetoacetate Ethy acetoacetate Isopropyl ncetoacetata Aldehyde Acetaldehyde AldchydhOthor Methoxy acetaldehyde Furfural m-Nitrobenzaldehyde Ketm Acetonyl acetone Acetone Amine Diethylene tetramine Triethylene tetrunino Pipyridene Pyridene Nitrite Proplonitrilo Eaten of inorganic acids Trimethyl phosphate Triethyltgholphate Beta-me oxy ethyl carbon- Dimethyl sulfate Amide:

Propionamlde Butyramide Him Nitromeihano Nitroethauo 7 Various ratios of solvent to oil may be employed in the extraction, but a ratio of about 1 to 1 seems to be satisfactory, but this ratio may be substantially increased or decreased if so desired. The temperature of extraction preferably is substantially below that of miscibility of the glyceridesin the 011 being extracted. But little difficulty will be encountered in maintaining sumciently low temperature because in the presencee of water solubility of the oils in the solvents is very limited, except at fairly elevated temperatures. Most of the extractions can be eflected quite conveniently ator near normal atmospheric temperatures. Degumming of soya bean oil with 4 aqueous furfural may be effected at 80 or 90 F.

The aqueous medium may be water alone or an aqueous solution of an alkaline salt, such as sodium carbonate or a 25% solution of sodium phosphate. Contact of the oil with aqueous sol-v vent results in precipitation of the lecithin sludge in the oil from which it can be removed by centotal volume of the latter. where large volumes of water are employed withfurfural, only a limited amount will dissolve, the remainder will be maintained as a third phase in the system.

The extracted oil can be employed for various purposes, but it is particularly suitable for further extraction by the processes disclosed in my foregoing patents for purposes of fractionating it upon the basis of unsaturation.

The acids as previously indicated can be used for various purposes including themanufacture of soap and the manufacture of modified resins. Lecithin is useful for addition to food products, as emulsifying agent and for numerous other pures. What I claim is: l. The process of obtaining a fraction rich in phosphatides and a fraction rich in free fatty acids from glyceride oils, which process comprises intimately contacting the oil with furfural approximately saturated with water to obtain a piurality of liquid phases, one consisting of furfural and water containing the free fatty acids and the other consisting primarily of oil with the phosphatides precipitated as a suspension therein,

then separating off the phases and separating the phosphatides from the oil.

2. A process as defined in claim 1, in which the glyceride oil undergoing treatment is soya bean so Oil.

STEPHEN E. FREEMAN. 

